Method of communicating a VMEbus signal over IP packet network

ABSTRACT

A method of communicating a VMEbus transfer ( 235 ) from an initiator VMEbus domain ( 202 ) over an IP packet network ( 210 ) to a responder VMEbus domain ( 204 ) can include the initiator VMEbus domain creating the VMEbus transfer and reading a VMEbus destination address ( 452 ) of the VMEbus transfer. The VMEbus destination address can be mapped to a responder VMEbus domain IP address and the VMEbus transfer encapsulated in an IP packet ( 236 ). The IP packet can be communicated to the responder VMEbus domain over the IP packet network.

BACKGROUND OF THE INVENTION

In current high-speed data networks, such as parallel multi-drop busnetworks using VERSAmodule Eurocard (VMEbus) protocols, signal integrityand maximum transfer speeds are limited by the number of slots occupiedby payload cards, the distance between payload cards, signal degradationon the parallel bus, and the like. Due to the myriad of factorsaffecting signal integrity on the parallel bus, it is difficult toextend VMEbus network beyond a short distance, such as a single chassis.In addition, improvements in protocols used on VMEbus networks are toocostly, and just cannot meet the rapidly increasing bandwidth demandsover the next few years.

Internet Protocol (IP) is the world's most popular open-system(nonproprietary) protocol suite because it can be used to communicateacross any set of interconnected networks and is equally well suited forLAN and WAN communications. While VMEbus will remain common in embedded,local network applications, IP will likely remain the network standardfor external networks such as the Internet. The prior art does notprovide a means to transport VMEbus transfers over the ubiquitous IPnetwork. This has the disadvantage in limiting the venerable VMEbus touse in single chassis and smaller networks.

Accordingly, there is a significant need for an apparatus and methodthat overcomes the deficiencies of the prior art outlined above.

BRIEF DESCRIPTION OF THE DRAWINGS

Referring to the drawing:

FIG. 1 depicts a computer network according to one embodiment of theinvention;

FIG. 2 depicts a computer network according to another embodiment of theinvention;

FIG. 3 depicts a ladder diagram illustrating an embodiment of theinvention;

FIG. 4 depicts a VMEbus transfer encapsulated into an IP packetaccording to an embodiment of the invention;

FIG. 5 illustrates a flow diagram of a method of the invention accordingto an embodiment of the invention; and

FIG. 6 illustrates a flow diagram of a method of the invention accordingto another embodiment of the invention.

It will be appreciated that for simplicity and clarity of illustration,elements shown in the drawing have not necessarily been drawn to scale.For example, the dimensions of some of the elements are exaggeratedrelative to each other. Further, where considered appropriate, referencenumerals have been repeated among the Figures to indicate correspondingelements.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following detailed description of exemplary embodiments of theinvention, reference is made to the accompanying drawings, whichillustrate specific exemplary embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice the invention, but otherembodiments may be utilized and logical, mechanical, electrical andother changes may be made without departing from the scope of thepresent invention. The following detailed description is, therefore, notto be taken in a limiting sense, and the scope of the present inventionis defined only by the appended claims.

In the following description, numerous specific details are set forth toprovide a thorough understanding of the invention. However, it isunderstood that the invention may be practiced without these specificdetails. In other instances, well-known circuits, structures andtechniques have not been shown in detail in order not to obscure theinvention.

For clarity of explanation, the embodiments of the present invention arepresented, in part, as comprising individual functional blocks. Thefunctions represented by these blocks may be provided through the use ofeither shared or dedicated hardware, including, but not limited to,hardware capable of executing software. The present invention is notlimited to implementation by any particular set of elements, and thedescription herein is merely representational of one embodiment.

FIG. 1 depicts a computer network 100 according to one embodiment of theinvention. Computer network 100 can include an IP packet network 110coupled to a gateway controller 112. IP packet network 110 can operateusing a suite of communication protocols known in the art, of which thetwo best known are the Transmission Control Protocol (TCP) and theInternet Protocol (IP). The Internet protocol suite not only includeslower-layer protocols (such as TCP and IP), but can also specify commonapplications such as electronic mail, terminal emulation, and filetransfer.

The Internet Protocol is a network-layer protocol that containsaddressing information and some control information that enables packetsto be routed. IP is the primary network-layer protocol in the Internetprotocol suite. Along with the Transmission Control Protocol, IPrepresents the heart of the Internet protocols. IP has two primaryresponsibilities: providing connectionless, best-effort delivery ofpackets through an internetwork of nodes; and providing fragmentationand reassembly of packets to support data links with differentmaximum-transmission unit (MTU) sizes.

Gateway controller 112 can be used to allow individual nodes coupled toIP packet network 110 to extract their configurations. In other words,individual nodes coupled to IP packet network 110 can extract theirconfiguration from gateway controller 112. In an example, gatewaycontroller 112 may not have any information on an individual nodecoupled to IP packet network 110 until that individual node requestsinformation. An example of gateway controller 112 can be a Dynamic HostConfiguration Protocol (DHCP) server. DHCP is an Internet protocol forautomating the configuration of computers that use TCP/IP. DHCP can beused to automatically assign IP addresses, to deliver TCP/IP stackconfiguration parameters such as the subnet mask and default router, andto provide other configuration information for example addresses forprinter, time and news servers.

VMEbus as known in the art, can be implemented as a master/slavearchitecture that uses an asynchronous bus with a variable speedhandshaking protocol. VMEbus is defined in the ANSI/VITA 1-1994 andANSI/VITA 1.1-1997 standards, promulgated by the VMEbus InternationalTrade Association (VITA), P.O. Box 19658, Fountain Hills, Ariz., 85269(where ANSI stands for American National Standards Institute). In anembodiment of the invention, VMEbus parallel multi-drop protocols caninclude, but are not limited to, Single Cycle Transfer protocol (SCT),Block Transfer protocol (BLT), Multiplexed Block Transfer protocol(MBLT), Two Edge VMEbus protocol (2 eVME) and Two Edge SourceSynchronous Transfer protocol (2eSST).

Computer network 100 can include any number of VMEbus domains 102, 104coupled to IP packet network 110. By way of example, VMEbus domain 102can include any number of boards, chassis, networks or systems thatinclude one or more VMEbus computing elements 130 coupled by a VMEbusnetwork 106. VMEbus network 106 is known in the art and can include anasynchronous bus operating a VMEbus protocol.

VMEbus computing element 130 can include, but is not limited to, aprocessor, memory device, storage device, wireline or wirelesscommunication device, and the like. For example, VMEbus computingelement 130 can be a blade in a VMEbus chassis that interfaces withVMEbus network 106. VMEbus computing element 130, can be for example andwithout limitation, a VMEbus blade with one or more processors operatingusing a PCI or PCI-X bus network as is known in the art. VMEbuscomputing element 130 is coupled to communicate on VMEbus network 106using VMEbus transfers generated and propagated using any VMEbusprotocol. In an embodiment, each VMEbus computing element 130 is coupledto VMEbus network 106. In an embodiment, VMEbus network 106 is coupledto VMEbus-to-IP bridge 103 which can function to encapsulate andde-encapsulate VMEbus transfers in and out of IP packets as explainedmore fully below.

In an embodiment, computer network 100 can include a plurality of VMEbusaddresses 117, which are only recognizable and readable within a VMEbusdomain 102, 104 operating a VMEbus network 106, 108. VMEbus addresses117 can each include, for example and without limitation, one or morememory address spaces as is known in the art. For example, plurality ofVMEbus addresses 117 may only be recognizable and relevant to VMEbuscomputing elements 130 coupled to VMEbus network 106 on VMEbus domain102 as they reference one or more unique memory address-spaces. Also,VMEbus domain 104 can have a set of VMEbus addresses relevant to VMEbuscomputing elements 132 coupled to VMEbus network 108.

In an embodiment, computer network 100 can also include IP packetnetwork domain 109 comprising a plurality of nodes having IP addresses.Plurality of IP addresses are recognizable and relevant on IP packetnetwork 110 within computer network 100.

Although VMEbus addresses 117 can be used to specify a destinationaddress for a VMEbus transfer going from one VMEbus domain 102 toanother VMEbus domain 104, these VMEbus addresses 117 are notrecognizable to IP packet network 110. Therefore, any VMEbus transferaddressed from one VMEbus domain 102 to another VMEbus domain 104 cannottravel over IP packet network 110 by itself.

In an embodiment, VMEbus domain 102 can include VMEbus-to-IP bridge 103coupled to VMEbus network 106 and to IP packet network 110. In anembodiment, VMEbus-to-IP bridge 103 can include any combination ofhardware, software, and the like. VMEbus-to-IP bridge 103 can functionto encapsulate a VMEbus transfer into an IP packet for transport over IPpacket network 110. VMEbus-to-IP bridge 103 can also function tode-encapsulate a VMEbus transfer from an IP packet so the VMEbustransfer can be communicated over VMEbus network 106.

VMEbus domain 104 can also include any number of VMEbus computingelements 132 coupled by VMEbus network 108. VMEbus domain 104 can alsoinclude. VMEbus-to-IP bridge 105 that functions to encapsulate andde-encapsulate a VMEbus transfer in a manner analogous to that describedwith reference to VMEbus-to-IP bridge 103 in VMEbus domain 102.

An exemplary embodiment of a method of initializing computer network 100is depicted in FIG. 1. In an embodiment, upon power-up or boot-up ofcomputer network 100, VMEbus domain 102 determines a VMEbus domainaddress map 114, which can be for example a list of all VMEbus addressesof each of the VMEbus computing elements 130 in VMEbus domain 102. In anembodiment, VMEbus domain address map 114 can be a list of the VMEbusaddresses of all VMEbus computing elements 130 capable of sending,receiving, and the like, a VMEbus transfer. The same procedure can berepeated for VMEbus domain 104 which can generate VMEbus domain addressmap 116 in an analogous manner.

In an embodiment, also upon power-up or boot-up of computer network 100,each VMEbus domain 102, 104 can request and receive from gatewaycontroller 112, an IP address 118, 120. For example, VMEbus domain 102can request IP address 118 and VMEbus domain 104 can request IP address120. Each IP address for each VMEbus domain in computer network 100 canbe unique so as to uniquely identify each VMEbus domain on IP packetnetwork 110. As is known in the art, an IP address can be used touniquely identify a node that is making use of IP packet network 110.The IP address can be used by the IP packet network 110 to direct datato each VMEbus domain 102, 104. In one embodiment, it can be the task ofgateway controller 112 to get a functional and unique IP address to eachVMEbus domain 102, 104 that makes use of IP packet network 110. Inanother embodiment, gateway controller 112 does not assign IP addressesas IP addresses for each of VMEbus domains 102, 104 can be static ordetermined at the VMEbus domain itself.

In an embodiment, gateway controller 112 can query each VMEbus domain incomputer network 100 to communicate its VMEbus domain address map. Forexample, gateway controller 112 can determine if a node in computernetwork 100 is a VMEbus domain. If it is, then gateway controller 112can request that the VMEbus domain communicate its VMEbus domain addressmap. For example, gateway controller 112 can query VMEbus domain 102 tocommunicate VMEbus domain address map 114 to gateway controller 112.Also, VMEbus domain 104 can be queried and send VMEbus domain addressmap 116 to gateway controller 112.

Upon receipt of all VMEbus domain address maps from VMEbus domains incomputer network 100, gateway controller 112 can build an IP-to-VMEbusdomain address map 122. In an embodiment IP-to-VMEbus domain map 122corresponds each VMEbus address 117 to an IP address 118, 120 where theVMEbus computing element 130; 132 resides. For example, IP-to-VMEbusdomain map 122 can match IP address 118 for VMEbus domain 102 to theVMEbus address 117 for each VMEbus computing element 130 in VMEbusdomain 102. Also, IP-to-VMEbus domain map 122 can match IP address 120for VMEbus domain 104 to the VMEbus address 117 for each VMEbuscomputing element 132 on VMEbus domain 104. In an embodiment,IP-to-VMEbus domain map 122 can correlate an IP address of a VMEbusdomain to a VMEbus address and memory size for that VMEbus domain.

In an embodiment, after gateway controller 112 builds IP-to-VMEbusdomain address map 122, gateway controller 112 can communicateIP-to-VMEbus domain map 122 to each VMEbus domain 102, 104 in computernetwork 100. For example, gateway controller 112 can communicateIP-to-VMEbus domain map 122 to VMEbus-to-IP bridge 103 on VMEbus domain102, and to VMEbus-to-IP bridge 105 on VMEbus domain 104.

The invention is not limited to computer networks having only VMEbusdomains. Computer network 100 can include other nodes coupled to IPpacket network 110 that function using another protocol besides VMEbus.

FIG. 2 depicts a computer network 200 according to another embodiment ofthe invention. In an embodiment, the computer network 200 of FIG. 2depicts a method of communicating a VMEbus transfer 235 from aninitiator VMEbus domain 202 to a responder VMEbus domain 204 over an IPpacket network 210. Computer network 200 can include VMEbus addresses217 in each of the VMEbus domains, and IP packet network domain 209 withIP addresses as discussed above with reference to FIG. 1.

As shown in FIG. 2, computer network 200 can include IP packet network210 coupled to initiator VMEbus domain 202 and responder VMEbus domain204. Initiator VMEbus domain 202 can include one or more VMEbuscomputing elements 230. VMEbus computing element 230 can include, but isnot limited to, a processor, memory device, storage device, wireline orwireless communication device, and the like. VMEbus computing element230 is coupled to communicate on VMEbus network 206 using VMEbustransfer 235.

VMEbus network 206 is coupled to VMEbus-to-IP bridge 203, which iscoupled to encapsulate a VMEbus transfer 235 into an IP packet 236 fortransport over IP packet network 210. VMEbus-to-IP bridge 203 can alsofunction to de-encapsulate a VMEbus transfer 235 from an IP packet 236so the VMEbus transfer 235 can be communicated over VMEbus network 206.

Responder VMEbus domain 204 can include one or more VMEbus computingelements 232. VMEbus computing element 232 is coupled to communicate onVMEbus network 208 using VMEbus transfer 235. VMEbus network 208 iscoupled to VMEbus-to-IP bridge 205, which is coupled to encapsulate aVMEbus transfer 235 into an IP packet 236 for transport over IP packetnetwork 210. VMEbus-to-IP bridge 205 can also function to de-encapsulatea VMEbus transfer 235 from an IP packet 236 so the VMEbus transfer 235can be communicated over VMEbus network 208.

As described with reference to FIG. 1, an initiator VMEbus domain IPaddress 240 can be communicated to initiator VMEbus domain 202 fromgateway controller 212 or otherwise statically determined. Also,responder VMEbus domain IP address 242 can be communicated to responderVMEbus domain 204 from gateway controller 212 or otherwise staticallydetermined. Further, as described with reference to FIG. 1, IP-to-VMEbusdomain map 222 can be determined and communicated to both initiatorVMEbus domain 202 and responder VMEbus domain 204.

In an embodiment, VMEbus computing element 230 at initiator VMEbusdomain 202 can create VMEbus transfer 235. In an embodiment, VMEbustransfer 235 can include any transfer addressed to another VMEbuscomputing element. If VMEbus transfer 235 is addressed to computingelement 232 in responder VMEbus domain 204, then VMEbus transfer 235 isrequired to traverse IP packet network 210 as shown in FIG. 2.

VMEbus transfer 235 can be communicated over VMEbus network 206 atinitiator VMEbus domain 202 to VMEbus-to-IP bridge 203, where the VMEbusdestination address is read. In an embodiment, VMEbus-to-IP bridge 203can use IP-to-VMEbus domain map 222 to map the VMEbus destinationaddress to responder VMEbus domain IP address 242. In an embodiment,responder VMEbus domain IP address 242 can be included in a header ofthe IP packet 236. In a further embodiment, VMEbus-to-IP bridge 203 ofinitiator VMEbus domain 202 can examine VMEbus transfer 235 to determineat least one VMEbus protocol flag to include in the IP packet 236. Forexample, the protocol used in VMEbus transfer 235 can be determined andplaced in IP packet 236 as a VMEbus protocol flag. In accordance withmapping, VMEbus transfer 235 can be encapsulated in an IP packet 236,where IP packet 236 is communicated to responder VMEbus domain 204 overIP packet network 210.

In an embodiment, upon receipt of IP packet 236 at responder VMEbusdomain 204, VMEbus-to-IP bridge 205 can de-encapsulate VMEbus transfer235 from IP packet 236. Thereafter, VMEbus transfer 235 can be issuedvia VMEbus network 208 to VMEbus computing element 232 corresponding tothe VMEbus destination address 217.

FIG. 3 depicts a ladder diagram illustrating an embodiment of theinvention. In an embodiment, initiator VMEbus domain 302 can initiate aread request, write data, control transfer, and the like, to responderVMEbus domain 304. Read, write and control transfers are known in theart and can include any type of electronic transfer that isunderstandable by responder VMEbus domain 304.

In an embodiment, a VMEbus computing element at initiator VMEbus domain302 can initiate communication with responder VMEbus domain 304 using acompelled (i.e. handshake) signaling process. The compelled (handshake)signaling process can be used with any VMEbus protocol. VMEbus transfer235 can include any transfer sent from one VMEbus computing element toanother VMEbus computing element. As shown in FIG. 3, the compelledsignaling process can begin with initiator VMEbus domain 302 initiatingcommunication with responder VMEbus domain 304 by sending request signal329, which can include the address of the targeted VMEbus computingelement at responder VMEbus domain 304, protocol to be used, and thelike. In an embodiment, the protocol to be used for data transfer can beindicated using extended address modifier (XAM) code. XAM code is knownin the art. In an embodiment, the VMEbus transaction can be a writetransaction, where request signal 329 can include data to be writtenfrom initiator VMEbus domain 302 to responder VMEbus domain 304. If theVMEbus computing element at responder VMEbus domain 304 recognizesrequest signal 329, responder VMEbus domain 304 can communicate responsesignal 331 back to initiator VMEbus domain 302 to indicate that data hasbeen written. Response signal 331 can also include a bus busy indicationor an error indication as is known in the art.

In another embodiment, the VMEbus transaction can be a read requesttransaction, where request signal 329 includes a request to read datafrom responder VMEbus domain 304. In this embodiment, response signal331 can include data read from responder VMEbus domain 304 that is beingcommunicated to initiator VMEbus domain 302. Response signal 331 canalso include a bus busy indication or an error indication as is known inthe art.

In an embodiment, each of the aforementioned signals, request signal 329or response signal 331 can be considered a VMEbus transfer 235 as eachare a communication from one VMEbus computing element to another VMEbuscomputing element or from one VMEbus domain to another VMEbus domain.

Request signal 329 and response signal 331 together can represent oneVMEbus transaction. Other types of VMEbus transfers or communicationsignals can be included in a VMEbus transaction and be within the scopeof the invention. Request signal 329 and response signal 331 can berepeated as often as necessary to read or write desired data from oneVMEbus domain to another VMEbus domain and be within the scope of theinvention.

As shown in FIG. 3, when going from one VMEbus domain to another VMEbusdomain, VMEbus transfers 235 can traverse IP packet network 310 and IPpacket network domain 309. VMEbus transfers 235 cannot by themselvestraverse IP packet network 310 or IP packet network domain 309.Therefore, encapsulating and de-encapsulating VMEbus transfers 235 asdescribed above can be used to communicate VMEbus transfer 235 frominitiator VMEbus domain 302 to responder VMEbus domain 304 over IPpacket network 310.

FIG. 4 depicts a VMEbus transfer 435 encapsulated into an IP packet 436according to an embodiment of the invention. In general, individualfields of an IP packet 436 are known in the art. The IP header 470 caninclude things such as the destination IP address, source address,packet length, and the like. Protocol information 472 can include aVMEbus protocol flag 451 used to indicate what VMEbus protocol is beingused in VMEbus transfer, VMEbus protocol version, and the like,including what upper layer protocol is to receive incoming packets afterIP processing. Payload 474 can include any data in IP packet 436 and caninclude encapsulated transfers, for example VMEbus transfer 435.Checksum 478 can ensure packet integrity.

VMEbus transfer 435 can include address field 480, which can includeVMEbus destination address 452, protocol to be used and the like. Forexample, address field 480 can include data from a VMEbus addressencoding table as is known in the art. For example, VMEbus addressencoding table can include the geographic address, slot number of aVMEbus computing element, and the like. In an embodiment, address fieldcan include any data to address VMEbus transfer 435. Data field 482 caninclude the data being transported by VMEbus transfer 435.

In an embodiment, VMEbus transfer 435 can be created by a VMEbuscomputing element in an initiator VMEbus domain as described above. Inone embodiment, VMEbus transfer 435 can include a VMEbus destinationaddress 452 in address field 480. In an embodiment, VMEbus-to-IP bridgecan include IP-to-VMEbus domain map 422 to map VMEbus destinationaddress 452 to responder VMEbus domain IP address 442. In an embodiment,responder VMEbus domain IP address 442 can be placed in IP header 470such that IP packet 436 is addressed to responder VMEbus domaincorresponding with VMEbus destination address 452. In other words, IPpacket 436 can be addressed to responder VMEbus domain having VMEbuscomputing element to which VMEbus transfer 435 is destined. VMEbustransfer 435 can then be encapsulated in payload portion 474 of IPpacket 436 as shown in FIG. 4.

When IP packet 436 arrives at responder VMEbus domain, the reverse ofthe above process can occur. For example, VMEbus-to-IP bridge atresponder VMEbus domain can de-encapsulate VMEbus transfer 435.Thereafter, VMEbus transfer 435 can be communicated over VMEbus networkto VMEbus computing element.

FIG. 5 illustrates a flow diagram 500 of a method of the inventionaccording to an embodiment of the invention. In an embodiment, FIG. 5sets forth a method of initializing a computer network. In step 502, aVMEbus domain determines a VMEbus domain address map for the VMEbuscomputing elements at VMEbus domain. In step 504, VMEbus domain requestsan IP address from gateway controller of an IP packet network. In step506, gateway controller issues an IP address to VMEbus domain.Optionally, steps 504 and 506 can be replaced with the step of theVMEbus domain generating its own static IP address or receiving an IPaddress from another source.

In step 508, gateway controller can request and receive VMEbus domainaddress map from VMEbus domain. Gateway controller can first determineif a node coupled to IP packet network is a VMEbus domain beforerequesting VMEbus domain address map. In step 510, gateway controllercan build an IP-to-VMEbus domain map based on the VMEbus domain addressmap. In step 512, gateway controller can communicate IP-to-VMEbus domainmap to VMEbus domain. The above steps illustrated in FIG. 5 can occurfor any number of VMEbus domains coupled to IP packet network.

FIG. 6 illustrates a flow diagram 600 of a method of the inventionaccording to another embodiment of the invention. In an embodiment, FIG.6 sets forth a method of communicating a VMEbus transfer from aninitiator VMEbus domain, over an IP packet network, to a responderVMEbus domain. In step 602, a VMEbus transfer is created by a VMEbuscomputing element at initiator VMEbus domain. In step 604, aVMEbus-to-IP bridge can read VMEbus destination address from VMEbustransfer.

In step 606, IP-to-VMEbus domain map at initiator VMEbus domain can beused to map VMEbus destination address to a responder VMEbus domain IPaddress. In step 608, VMEbus transfer can be encapsulated in an IPpacket. In step 610, IP packet can be communicated over IP packetnetwork to responder VMEbus domain. In step 612, VMEbus transfer can bede-encapsulated from IP packet at VMEbus-to-IP bridge at responderVMEbus domain. In step 614, VMEbus transfer can be issued to a VMEbuscomputing element over a VMEbus network on responder VMEbus domain.

While we have shown and described specific embodiments of the presentinvention, further modifications and improvements will occur to thoseskilled in the art. It is therefore, to be understood that appendedclaims are intended to cover all such modifications and changes as fallwithin the true spirit and scope of the invention.

1. In a computer network, a method of communicating a VMEbus transfer from an initiator VMEbus domain over an IP packet network to a responder VMEbus domain, comprising: the initiator VMEbus domain creating the VMEbus transfer; reading a VMEbus destination address of the VMEbus transfer; mapping the VMEbus destination address to a responder VMEbus domain IP address; encapsulating the VMEbus transfer in an IP packet; and communicating the IP packet to the responder VMEbus domain over the IP packet network.
 2. The method of claim 1, further comprising: the responder VMEbus domain de-encapsulating the VMEbus transfer from the IP packet; and issuing the VMEbus transfer to a VMEbus computing element having the VMEbus destination address.
 3. The method of claim 1, further comprising placing a VMEbus protocol flag in the IP packet.
 4. The method of claim 1, further comprising placing the responder VMEbus domain IP address into an IP header of the IP packet.
 5. A method of initializing a computer network, comprising: a VMEbus domain coupled to an IP packet network determining a VMEbus domain address map; the VMEbus domain requesting an IP address from a gateway controller of the IP packet network; the gateway controller assigning the IP address to the VMEbus domain; the gateway controller building an IP-to-VMEbus domain map based on the VMEbus domain address map; and the gateway controller communicating the IP-to-VMEbus domain map to the VMEbus domain.
 6. The method of claim 5, further comprising: the gateway controller determining the VMEbus domain; and if the gateway controller determines the VMEbus domain, the gateway controller requesting the VMEbus domain address map in order to build the IP-to-VMEbus domain map.
 7. The method of claim 5, wherein the VMEbus domain functions as an initiator VMEbus domain, the method further comprising: the initiator VMEbus domain creating a VMEbus transfer having a VMEbus destination address; mapping the VMEbus destination address to a responder VMEbus domain IP address; encapsulating the VMEbus transfer in an IP packet; and communicating the IP packet to the responder VMEbus domain over the IP packet network.
 8. A method of initializing a computer network, comprising: a plurality of VMEbus domains coupled to an IP packet network each determining one of a plurality of VMEbus domain address maps; each of the plurality of VMEbus domains requesting an IP address from a gateway controller of the IP packet network; the gateway controller assigning the IP address to each of the plurality of VMEbus domains; the gateway controller building an IP-to-VMEbus domain map using the plurality of VMEbus domain address maps corresponding to each the plurality of VMEbus domains; and the gateway controller communicating IP-to-VMEbus domain map to the plurality of VMEbus domains.
 9. The method of claim 8, wherein one of the plurality of VMEbus domains functions as an initiator VMEbus domain and one of the plurality of VMEbus domains functions as a responder VMEbus domain, the method further comprising: the initiator VMEbus domain creating a VMEbus domain transfer having a VMEbus destination address; mapping the VMEbus destination address to a responder VMEbus domain IP address; encapsulating the VMEbus transfer in an IP packet; and communicating the IP packet to the responder VMEbus domain over the IP packet network.
 10. A VMEbus domain, comprising: a VMEbus network having at least one VMEbus computing element; and a VMEbus-to-IP bridge coupled to the VMEbus network, wherein the VMEbus-to-IP bridge couples the VMEbus domain to an IP packet network, wherein the VMEbus-to-IP bridge is coupled to determine a VMEbus domain address map of the VMEbus network, wherein the VMEbus-to-IP bridge is coupled to request an IP address from a gateway controller of the IP packet network, wherein the VMEbus-to-IP bridge is coupled to map a VMEbus destination address to a responder VMEbus domain IP address, and wherein the VMEbus-to-IP bridge is coupled to encapsulate a VMEbus transfer generated from the VMEbus network into an IP packet.
 11. The VMEbus domain of claim 10, wherein the VMEbus-to-IP bridge is coupled to communicate the IP packet to a responder VMEbus domain over the IP packet network.
 12. In a VMEbus domain, a method of communicating a VMEbus transfer over an IP packet network, comprising: creating the VMEbus transfer; reading a VMEbus destination address of the VMEbus transfer; mapping the VMEbus destination address to a responder VMEbus domain IP address; encapsulating the VMEbus transfer in an IP packet; and communicating the IP packet to a responder VMEbus domain over the IP packet network.
 13. The VMEbus domain of claim 12, further comprising placing a VMEbus protocol flag in the IP packet.
 14. The VMEbus domain of claim 12, further comprising placing the responder VMEbus domain IP address into an IP header of the IP packet.
 15. In a VMEbus domain, a method of communicating a VMEbus transfer over an IP packet network, comprising: receiving an IP packet over the IP packet network, wherein the IP packet comprises the VMEbus transfer; de-encapsulating the VMEbus transfer from the IP packet; and issuing the VMEbus transfer to a VMEbus computing element having a VMEbus destination address.
 16. In a VMEbus domain, a method of initializing an IP packet network, comprising: determining a VMEbus domain address map; requesting and receiving an IP address from a gateway controller of the IP packet network; communicating the VMEbus domain address map to the gateway controller; the gateway controller building an IP-to-VMEbus domain map based on the VMEbus domain address map; and the gateway controller communicating the IP-to-VMEbus domain map to the VMEbus domain.
 17. A computer-readable medium containing computer instructions for instructing a processor to perform a method of communicating a VMEbus transfer from an initiator VMEbus domain over an IP packet network to a responder VMEbus domain, the instructions comprising: the initiator VMEbus domain creating the VMEbus transfer; reading a VMEbus destination address of the VMEbus transfer; mapping the VMEbus destination address to a responder VMEbus domain IP address; encapsulating the VMEbus transfer in an IP packet; and communicating the IP packet to the responder VMEbus domain over the IP packet network.
 18. The computer-readable medium of claim 17, further comprising: the responder VMEbus domain de-encapsulating the VMEbus transfer from the IP packet; and issuing the VMEbus transfer to a VMEbus computing element having the VMEbus destination address.
 19. The computer-readable medium of claim 17, further comprising placing a VMEbus protocol flag in the IP packet.
 20. The computer-readable medium of claim 17, further comprising placing the responder VMEbus domain IP address into an IP header of the IP packet.
 21. A computer-readable medium containing computer instructions for instructing a processor to perform a method of initializing a computer network, the instructions comprising: a VMEbus domain coupled to an IP packet network determining a VMEbus domain address map; the VMEbus domain requesting an IP address from a gateway controller of the IP packet network; the gateway controller assigning the IP address to the VMEbus domain; the gateway controller building an IP-to-VMEbus domain map based on the VMEbus domain address map; and the gateway controller communicating the IP-to-VMEbus domain map to the VMEbus domain.
 22. The computer-readable medium of claim 21, further comprising: the gateway controller determining the VMEbus domain; and if the gateway controller determines the VMEbus domain, the gateway controller requesting the VMEbus domain address map in order to build the IP-to-VMEbus domain map.
 23. The computer-readable medium of claim 21, wherein the VMEbus domain functions as an initiator VMEbus domain, the computer-readable medium instructions further comprising: the initiator VMEbus domain creating a VMEbus transfer having a VMEbus destination address; mapping the VMEbus destination address to a responder VMEbus domain IP address; encapsulating the VMEbus transfer in an IP packet; and communicating the IP packet to the responder VMEbus domain over the IP packet network.
 24. A computer-readable medium containing computer instructions for instructing a processor to perform a method of initializing a computer network, the instructions comprising: a plurality of VMEbus domains coupled to an IP packet network each determining one of a plurality of VMEbus domain address maps; each of the plurality of VMEbus domains requesting an IP address from a gateway controller of the IP packet network; the gateway controller assigning the IP address to each of the plurality of VMEbus domains; the gateway controller building an IP-to-VMEbus domain map using the plurality of VMEbus domain address maps corresponding to each the plurality of VMEbus domains; and the gateway controller communicating IP-to-VMEbus domain map to the plurality of VMEbus domains.
 25. The computer-readable medium of claim 24, wherein one of the plurality of VMEbus domains functions as an initiator VMEbus domain and one of the plurality of VMEbus domains functions as a responder VMEbus domain, the method further comprising: the initiator VMEbus domain creating a VMEbus domain transfer having a VMEbus destination address; mapping the VMEbus destination address to a responder VMEbus domain IP address; encapsulating the VMEbus transfer in an IP packet; and communicating the IP packet to the responder VMEbus domain over the IP packet network.
 26. In a VMEbus domain, a computer-readable medium containing computer instructions for instructing a processor to perform a method of communicating a VMEbus transfer over an IP packet network, comprising: creating the VMEbus transfer; reading a VMEbus destination address of the VMEbus transfer; mapping the VMEbus destination address to a responder VMEbus domain IP address; encapsulating the VMEbus transfer in an IP packet; and communicating the IP packet to a responder VMEbus domain over the IP packet network.
 27. In a VMEbus domain, a computer-readable medium containing computer instructions for instructing a processor to perform a method of communicating a VMEbus transfer over an IP packet network, comprising: receiving an IP packet over the IP packet network, wherein the IP packet comprises the VMEbus transfer; de-encapsulating the VMEbus transfer from the IP packet; and issuing the VMEbus transfer to a VMEbus computing element having a VMEbus destination address.
 28. In a VMEbus domain, a computer-readable medium containing computer instructions for instructing a processor to perform a method of initializing an IP packet network, comprising: determining a VMEbus domain address map; requesting and receiving an IP address from a gateway controller of the IP packet network; communicating the VMEbus domain address map to the gateway controller; the gateway controller building an IP-to-VMEbus domain map based on the VMEbus domain address map; and the gateway controller communicating the IP-to-VMEbus domain map to the VMEbus domain. 